How can I record a Behringer UCG102 Guitar Link, an ASIO device, with audio toolbox

Hello,

I'm trying to read out the input signal of a Behringer UCG102 Guitar Link using the audio toolbox.

This is what I've done so far:

asiosettings() % opens the asiodriver UI
pause 

deviceReader = audioDeviceReader();
devices = getAudioDevices(deviceReader);

deviceReader.Driver = 'asio';               %'DirectSound','WASAPI','asio'
deviceReader.Device = 'BEHRINGER USB AUDIO';%'defaulu audio device','BEHRINGER USB AUDIO','ASIO4ALL v2'
deviceReader.NumChannels = 2;
deviceReader.SamplesPerFrame = 1024;
deviceReader.SampleRate = 44100;
deviceReader.BitDepth = '16-bit integer';   %'16-bit integer','8-bit integer','32-bit float','24-bit integer'
deviceReader.ChannelMappingSource = 'Auto'; % 'Auto','Property'
deviceReader.ChannelMapping = [1,1];
deviceReader.OutputDataType = 'double';

setup(deviceReader);

[AUDIO, NUMOVERRUN] = record(deviceReader);
audioFromDevice = deviceReader();

Each of the last two lines should return a Matrix with one Frame of each Channel, if I'm not mistaken. And they actually return a 1024x2-matrix, but they both contain just a noise signal. Can somebody point out where my mistake is?

Thank you.

Peter